The Longitudinal Assessment of Bariatric Surgery (LABS) Consortium was conceived to address important issues in bariatric surgery and metabolism in the obese and morbidly obese and is structured as a longitudinal observational study. The LABS Consortium is unique in that it has assembled a large, heterogeneous, multi-center, cohort of bariatric surgery patients with a research infrastructure characterized by standardized and rigorous data collection, data accuracy and completeness that is unique in bariatric surgery. The study is designed to prospectively and comprehensively follow 2400 bariatric patients post-surgery. The overarching goals of LABS for the five year renewal period focus on the accomplishment of stated targets for the LABS-2 protocol including the continued long term follow up of bariatric surgery participants to allow for the assessment of safety and efficacy, the ability to compare post-surgical outcomes to pre-operative status, and to examine the risks and benefits of surgery. Specific domains of longitudinal research interest in LABS-2 are weight loss and body composition, diabetes and insulin resistance, behavioral outcomes, quality of life, women's health and reproductive outcomes, and many others. In addition, LABS will continue to obtain and store biospecimens for research related to the aims of LABS-2, and for future research into the pathophysiology of obesity and obesity related complications. During a five year renewal period, the University of Pittsburgh, as an integral member of the LABS Consortium, will accomplish completed recruitment and optimal retention of subjects for longer-term follow up of stated outcomes, complete the Biospecimen Repository of blood, urine, and DNA samples for future research by the scientific community at large, bring results of LABS to the scientific community in areas including women's health and patient risk stratification, and maintain the infrastructure to allow Ancillary Studies reliant on LABS to meet their goals. RELEVANCE (See instructions): This project is an extension of the LABS grant, a longitudinal outcomes study following bariatric surgery, which aims to continue longer-term follow up of subjects, save important biospecimens for future study, and bring the results of weight loss outcomes studied to the scientific community. This study will bring important new knowledge about the outcomes and effects of bariatric surgery on many health conditions.